The National Park Service comprises 417 places. They include national parks as well as other types of sites — national monuments, battlefields and seashores, for example. To find the park nearest to you, visit the Park Service’s “Find a Park” page.

Most of the 417 sites do not charge entrance fees at any time. The 118 that do charge admission waive that cost on the entrance fee-free days.

National Park Service Deputy Director Michael T. Reynolds says in the announcement:

“The days that we designate as fee-free for national parks mark opportunities for the public to participate in service projects, enjoy ranger-led programs, or just spend time with family and friends exploring these diverse and special places. We hope that these fee-free days offer visitors an extra incentive to enjoy their national parks in 2018.”

Other types of fees, such as those for camping or special tours, still apply on free-entrance days.